Radomes function to protect antennas such as radar and other antennas and associated equipment from environmental exposure and thus must exhibit suitable structural integrity, be capable of surviving structural, thermal and other stresses, and, in the case of aircraft radomes, be aerodynamic in design. Radomes must also be constructed to achieve certain desired electrical performance characteristics. Electrical considerations include minimum transmission loss, minimum beam deflection, minimum pattern distortion, and minimum reflected power. Typically, there is a trade off in the design of a radome as between structural, environmental, and electrical considerations.
There are many different types of materials used in constructing radomes and many different cross sectional configurations including single layer (typically made of a composite material), A-sandwich, B-sandwich, C-sandwich, and multiple-layer sandwich constructions.
The B-sandwich configuration wherein a high density composite core layer is sandwiched between two lower density skin layers is not commonly used. See Rudge, A. W., K. Miene, A. D. Oliver, and P. Knight, The Handbook of Antenna Design, Vol. 2, Chapter 14, Peter Peregrenus Ltd., London, UK, and Skolnik, M. I., Introduction to Radar Systems, Chapter 7, McGraw-Hill, New York, N.Y. incorporated herein by this reference. The most likely reason is that the fairly rigid material which would typically serve as the skin layers cannot be easily processed along with the central load bearing, core layer during the fabrication of the radome.
Still, a B-sandwich radome structure is advantageous in some instances because it provides transparency over a wide variety of frequencies and incident angles and also provides thermal insulation for the structural core layer.